CN106542535B - Preparation method of early-strength concrete admixture - Google Patents
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- C01—INORGANIC CHEMISTRY
- C01B—NON-METALLIC ELEMENTS; COMPOUNDS THEREOF; METALLOIDS OR COMPOUNDS THEREOF NOT COVERED BY SUBCLASS C01C
- C01B33/00—Silicon; Compounds thereof
- C01B33/20—Silicates
- C01B33/24—Alkaline-earth metal silicates
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- C—CHEMISTRY; METALLURGY
- C04—CEMENTS; CONCRETE; ARTIFICIAL STONE; CERAMICS; REFRACTORIES
- C04B—LIME, MAGNESIA; SLAG; CEMENTS; COMPOSITIONS THEREOF, e.g. MORTARS, CONCRETE OR LIKE BUILDING MATERIALS; ARTIFICIAL STONE; CERAMICS; REFRACTORIES; TREATMENT OF NATURAL STONE
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- C01P—INDEXING SCHEME RELATING TO STRUCTURAL AND PHYSICAL ASPECTS OF SOLID INORGANIC COMPOUNDS
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Abstract
The invention discloses an early strength concrete admixture and a preparation method thereof, wherein the early strength concrete admixture comprises calcium silicate hydrate hollow nano particles. The preparation method of the early strength concrete admixture, namely the preparation method of the calcium silicate hydrate hollow nano particles, is prepared by interface reaction of water-soluble calcium salt in a dispersed phase, namely a water phase, and tetraethyl orthosilicate in a continuous phase, namely a non-polar solvent under the action of catalyst ammonia water. The early-strength concrete admixture has obvious early-strength effect; and the dosage is very small.
Description
The technical field is as follows:
the invention relates to an early strength concrete admixture, in particular to a calcium silicate hydrate hollow nanoparticle concrete early strength admixture prepared by utilizing an interfacial reaction, and belongs to the technical field of concrete admixtures.
Background art:
the early strength agent is an additive for accelerating early hydration of cement and improving early strength of concrete so as to meet construction and structure requirements. At present, global economic development is slowed down, environmental problems are increasingly prominent, early hydration of concrete is accelerated, early strength of the concrete is improved, economic benefits are improved, construction progress is accelerated, and emission of CO2 is reduced. Meanwhile, with the development of concrete technology, industrial waste is more and more widely applied to concrete as a basic raw material, and in order to reduce early hydration heat and improve concrete durability in the production of large prefabricated parts, a large amount of mineral admixtures such as mineral powder and fly ash are used, so that the early strength of the concrete is more slowly developed, and the process progress such as mold turnover, prestress loading and the like is influenced.
The nano calcium silicate hydrate is a common early strength agent, has a chemical structure similar to that of a cement hydration product C-S-H gel, can be used as a hydration product growth seed crystal to accelerate the early hydration reaction of cement, and has a remarkable early strength effect.
At present, calcium silicate hydrate is usually produced by directly reacting an aqueous solution of calcium nitrate and sodium silicate, and then a precipitate product is filtered and dried to produce calcium silicate hydrate powder. However, in practical application, the powder is difficult to uniformly disperse in concrete, and the early strength effect of the powder is influenced; in the presence of a dispersant, the aqueous solution of calcium nitrate and sodium silicate is selected to directly react to generate calcium silicate hydrate sol, and the sol is stable in storage and can be directly applied to the field of concrete.
For example, chinese patent CN201410593398 discloses a preparation method of calcium silicate hydrate sol as cement-based material early strength agent, which directly mixes and reacts an aqueous solution of calcium nitrate and sodium silicate in the presence of a dispersant, namely a naphthalenesulfonate formaldehyde condensate, to obtain a calcium silicate hydrate sol dispersion liquid, wherein the dispersion liquid is a stable liquid and has a certain early strength effect on cement paste.
Chinese patent CN201410591887 discloses that calcium nitrate and sodium silicate aqueous solution are directly mixed and reacted to obtain calcium silicate hydrate sol, and the calcium silicate hydrate sol dispersion is obtained by filtering the calcium silicate hydrate sol and dispersing the calcium silicate hydrate sol by using naphthalenesulfonate formaldehyde condensate.
The calcium silicate hydrate sol prepared by the method essentially utilizes the induction nucleation effect of the surface of the sol particle, the surface of the calcium silicate hydrate sol only plays the induction effect, and a large amount of substances in the calcium silicate hydrate sol cannot play the early strengthening effect, so that the doping amount is high, and the resource is wasted.
The invention content is as follows:
aiming at the defects that the existing hydrated calcium silicate early strength agent is difficult to effectively disperse or the mixing amount is too high, the invention provides the early strength agent with outstanding early strength effect and less dosage and the preparation method thereof.
The applicant finds that the calcium silicate hydrate is prepared into hollow nano particles, so that on one hand, the effect of inducing crystallization nucleation is retained, and the early strength effect is obvious; on the other hand, due to the hollow structure, the using amount can be greatly reduced.
Namely, the early strength concrete admixture of the invention comprises a calcium silicate hydrate hollow nano particle.
The early strength concrete admixture is prepared by the interfacial reaction of water soluble calcium salt in a dispersed phase, namely a water phase, and tetraethyl orthosilicate in a continuous phase, namely a non-polar solvent under the action of catalyst ammonia water.
The water-soluble calcium salt is calcium nitrate and calcium nitrite.
The non-polar solvent refers to cyclohexane, white oil and toluene.
The preparation method comprises the following steps:
firstly, preparing a water-soluble calcium salt, catalyst ammonia water and water into a solution, then mixing the aqueous solution and a nonpolar solvent containing an emulsifier and a co-stabilizer in a water bath at the temperature of 20-40 ℃, pre-emulsifying by high-speed stirring, and preparing an inverse miniemulsion by ultrasonic emulsification;
then slowly dripping tetraethyl orthosilicate (TEOS) into the emulsion for 5-10 hours, dissolving the TEOS into the continuous phase, and reacting the TEOS with calcium salt at the interface to generate a hydrated calcium silicate shell layer because catalyst ammonia exists in the dispersed phase when the TEOS is diffused to the interface of the continuous phase and the dispersed phase;
finally forming the calcium silicate hydrate hollow nano particles.
The emulsifier adopts a lipophilic nonionic surfactant, and the HLB is 3-8. The dosage of the emulsifier accounts for 3-5% of the whole system (emulsifier/(continuous phase + disperse phase (without inorganic salt))), and the emulsion with the expected particle size is not easy to obtain due to too small dosage of the emulsifier, and the stability is also poor.
The emulsifier is Span40, Span60, Span80 and a mixture of two or more of the emulsifiers according to any proportion.
The co-stabilizer adopts polyvinylpyrrolidone (PVP), Cetyl Trimethyl Ammonium Chloride (CTAC) and Cetyl Trimethyl Ammonium Bromide (CTAB).
The amount of the co-stabilizer accounts for 0.5-1% of the whole system (co-stabilizer/(continuous phase + dispersed phase (containing no inorganic salt))).
The co-stabilizer can be cooperated with the emulsifier to further improve the stability of the emulsion. After the synthesis is finished, the obtained hollow particles are dispersed in water, so that the stability can be achieved, and the storage stability and the use convenience are improved.
The preparation method mainly comprises the following three steps:
(1) firstly, inverse miniemulsion containing calcium salt and catalyst is prepared, which is prepared by mixing aqueous solution of water-soluble calcium salt and catalyst ammonia water with nonpolar solvent containing emulsifier and co-stabilizer under high-speed stirring and ultrasonic emulsification.
The dispersed phase is water solution of calcium salt and ammonia water. The ammonia water is an important catalyst for the reaction of TEOS and calcium salt, and the dosage of the ammonia water is 1-2% of the mass of TEOS. The water-soluble calcium salt comprises inorganic calcium salts which can be dissolved in water, such as calcium nitrate, calcium nitrite, calcium acetate and the like, and the mass concentration of the water-soluble calcium salts is 10-20%.
Increasing the concentration of the water-soluble calcium salt can relieve the Laplace pressure, so that the stability of the emulsion is improved to a certain extent, but when the mass concentration of the water-soluble calcium salt exceeds 20%, the stability of the emulsion is adversely affected.
The continuous phase adopts non-polar solvents which are not mutually soluble with water, such as cyclohexane, toluene, white oil and the like, and the mass ratio of the continuous phase to the whole system (continuous phase/(continuous phase + dispersed phase (containing inorganic salt))) is 50-70%.
Mixing the dispersed phase and the continuous phase, placing the mixture in a water bath at the temperature of 20-40 ℃, pre-emulsifying for 15 minutes under high-speed stirring, and then ultrasonically emulsifying for 15 minutes to finally obtain the inverse emulsion with the particle size of 50-200 nm, wherein the particles are too small to be realized under the conditions, the stability of the emulsion is not good, the specific surface area of the hollow particles finally obtained is small, the early strength performance is inevitably reduced under the same quality, and the application performance of the final product is influenced.
(2) Keeping the temperature at 20-40 ℃, dropwise adding TEOS within 5-10 h under the stirring condition, and continuing the heat preservation reaction for 24h after the dropwise adding is finished. The dosage of TEOS is determined by the dosage of calcium salt, and the Ca/Si molar ratio is required to be 2: 1-1: 1.
(3) And raising the temperature to 80 ℃ for demulsification, and collecting the aqueous phase to obtain the dispersion liquid of the prepared hydrated calcium silicate hollow nano particles.
The early strength agent of the invention provides nano-scale calcium silicate crystal nuclei required by the growth of early hydration crystals of cement, and shortens the time of supersaturation of liquid phase ions and crystal nucleus formation in the initial stage of hydration, thereby greatly accelerating the early hydration of cement. Meanwhile, the early strength agent is hollow nano particles, and compared with the conventional calcium silicate hydrate sol, the early strength agent removes the part of calcium silicate which does not play a crystal nucleation role in the interior, so that the doping amount is greatly reduced, and the effect is better.
The early strength agent does not contain chloride salt, has no corrosion effect on reinforcing steel bars in concrete, and does not influence the durability of the concrete. The early strength agent is an extremely stable suspension system, is convenient to add and is easy to uniformly disperse in the concrete preparation process. In addition, the early strength agent promotes the cement to generate a large amount of calcium hydroxide in an early age, is very beneficial to the activation of the mineral admixture, has a particularly obvious early strength effect on the concrete using the mineral admixture with a large mixing amount, is particularly suitable for the production of concrete prefabricated parts, and can effectively reduce or even eliminate a steam curing process.
Drawings
FIG. 1: TEM photographs of the samples obtained in example 1, example 2 and example 3 were synthesized.
The specific implementation mode is as follows:
the following examples describe in more detail the preparation of the polymer product according to the process of the invention and are given by way of illustration and are intended to enable one skilled in the art to understand the contents of the invention and to carry out the invention, without limiting the scope of the invention in any way. All equivalent changes and modifications made according to the spirit of the present invention should be covered within the protection scope of the present invention.
Synthesis example 1
Dissolving 50 g of calcium nitrate tetrahydrate and 0.55 g of ammonia water in 227.78 g of water, adding the solution into 648.15 g of cyclohexane dissolved with 43.80 g of Span80 and 7.88 g of PVP, pre-emulsifying for 15 minutes at a high speed of 25 ℃, and then ultrasonically emulsifying for 15 minutes to obtain an emulsion; slowly dripping 36.75 g TEOS into the emulsion within 7 hours at 25 ℃ under stirring, continuing to react for 24 hours after the dripping is finished, raising the temperature to 80 ℃ for demulsification, and collecting an aqueous phase to obtain the prepared calcium silicate hydrate hollow nanoparticle dispersion.
Synthesis example 2
Dissolving 50 g of calcium nitrate tetrahydrate and 0.59 g of ammonia water in 283.33 g of water, adding the solution into 676.77 g of cyclohexane dissolved with 43.20 g of Span80 and 7.68 g of CTAB, pre-emulsifying for 15 minutes at a high speed of 30 ℃, and then ultrasonically emulsifying for 15 minutes to obtain an emulsion; slowly dripping 29.40 g of TEOS into the emulsion within 6 hours at 30 ℃ while stirring, raising the temperature to 80 ℃ after the dripping is finished and continuing to react for 24 hours, demulsifying, and collecting an aqueous phase to obtain the prepared calcium silicate hydrate hollow nanoparticle dispersion.
Synthesis example 3
Dissolving 50 g of calcium nitrate tetrahydrate and 0.27 g of ammonia water in 366.67 g of water, adding the solution into 575.4 g of cyclohexane dissolved with 35.80 g of Span60 and 7.54 g of CTAC, pre-emulsifying for 15 minutes at a high speed of 35 ℃, and then ultrasonically emulsifying for 15 minutes to obtain an emulsion; slowly dripping 24.50 g TEOS into the emulsion within 5 hours at 35 ℃ while stirring, raising the temperature to 80 ℃ after the dripping is finished and continuously reacting for 24 hours, demulsifying, and collecting an aqueous phase to obtain the prepared calcium silicate hydrate hollow nano particle dispersion liquid.
Synthesis example 4
Dissolving 50 g of calcium nitrate tetrahydrate and 0.44 g of ammonia water in 283.33 g of water, adding the solution into 407.41 g of cyclohexane in which 22.10 g of Span40 and 3.45 g of PVP are dissolved, pre-emulsifying for 15 minutes at a high speed of 25 ℃, and then ultrasonically emulsifying for 15 minutes to obtain an emulsion; slowly dripping 36.75 g TEOS into the emulsion within 7 hours at 25 ℃ under stirring, continuing to react for 24 hours after the dripping is finished, raising the temperature to 80 ℃ for demulsification, and collecting an aqueous phase to obtain the prepared calcium silicate hydrate hollow nanoparticle dispersion.
Synthesis example 5
Dissolving 50 g of calcium nitrite dihydrate and 0.74 g of ammonia water in 283.33 g of water, adding the solution into 500.00 g of toluene dissolved with 27.42 g of Span60 and 5.48 g of PVP, pre-emulsifying for 15 minutes at a high speed of 25 ℃, and then ultrasonically emulsifying for 15 minutes to obtain an emulsion; slowly dripping 41.34 g TEOS into the emulsion within 8 hours at 25 ℃ under stirring, continuing to react for 24 hours after the dripping is finished, raising the temperature to 80 ℃ for demulsification, and collecting the aqueous phase to obtain the prepared calcium silicate hydrate hollow nanoparticle dispersion.
Synthesis example 6
Dissolving 50 g of calcium nitrite dihydrate and 0.65 g of ammonia water in 283.33 g of water, adding the solution into 500.00 g of cyclohexane in which 31.33 g of Span60 and 6.27 g of PVP are dissolved, pre-emulsifying for 15 minutes at a high speed of 25 ℃, and then ultrasonically emulsifying for 15 minutes to obtain an emulsion; slowly dripping 34.45 g TEOS into the emulsion within 7 hours at 25 ℃ under stirring, continuing to react for 24 hours after the dripping is finished, raising the temperature to 80 ℃ for demulsification, and collecting the aqueous phase to obtain the prepared calcium silicate hydrate hollow nanoparticle dispersion.
Synthesis example 7
Dissolving 50 g of calcium acetate and 0.57 g of ammonia water in 283.33 g of water, adding the solution into 500.00 g of white oil dissolved with 28.98 g of Span60 and 4.70 g of PVP, pre-emulsifying for 15 minutes at a high speed of 25 ℃, and then ultrasonically emulsifying for 15 minutes to obtain an emulsion; and slowly dripping 43.90 g of TEOS into the emulsion within 9 hours at 25 ℃ under stirring, continuing to react for 24 hours after the dripping is finished, raising the temperature to 80 ℃ for demulsification, and collecting an aqueous phase to obtain the prepared calcium silicate hydrate hollow nanoparticle dispersion.
Synthesis example 8
Dissolving 50 g of calcium acetate and 0.66 g of ammonia water in 283.33 g of water, adding the solution into 500.00 g of cyclohexane dissolved with 27.42 g of Span60 and 3.92 g of PVP, pre-emulsifying for 15 minutes at a high speed of 25 ℃, and then ultrasonically emulsifying for 15 minutes to obtain an emulsion; and slowly dripping 43.90 g of TEOS into the emulsion within 9 hours at 25 ℃ under stirring, continuing to react for 24 hours after the dripping is finished, raising the temperature to 80 ℃ for demulsification, and collecting an aqueous phase to obtain the prepared calcium silicate hydrate hollow nanoparticle dispersion.
Comparative Synthesis example
The comparative synthesis example is a solid calcium silicate hydrate early strength agent synthesized according to example two of chinese patent CN201410593398, and the concrete is as follows: 236 g of calcium nitrate tetrahydrate is weighed and dissolved in 1300 g of water, and after stirring for 20 seconds, 3.07 g of naphthalenesulfonate formaldehyde condensate (a commercially available standard high-efficiency water reducing agent) is added and stirring is continued for 30 seconds; weighing 284 g of sodium silicate nonahydrate, dissolving the sodium silicate nonahydrate into 1300 g of water, stirring for 20 seconds, adding 3.07 g of naphthalene sulfonate formaldehyde condensate (a commercially available standard high-efficiency water reducing agent), and continuously stirring for 30 seconds; stirring and mixing the two solutions for 360 seconds to prepare milk white gel-state liquid, namely the solid calcium silicate hydrate early strength agent
Application examples
Application example 1
The morphology of the resulting calcium silicate hydrate nano hollow particles was observed by a transmission electron microscope (TEM: JEM-200 CX; JEOL Co., Ltd., Japan), and a TEM photograph of the sample of example 1 is shown in FIG. 1, from which it can be seen that calcium silicate hydrate forms hollow spherical particles.
Application example 2
The concrete compressive strength test is carried out according to the concrete mixing ratio shown in the table 1, and the concrete raw materials are respectively reference cement (PI 52.5), II-grade fly ash and S95 ground slag powder which meet the national standard, river sand with the fineness modulus of 2.7 and 5-25mm continuous graded broken stone.
TABLE 1 concrete mix ratio (Kg/m)3)
| Cement | Mineral powder | Fly ash | Sand | Crushing stone | Water (W) |
| 337.5 | 45 | 67.5 | 700 | 1140 | 138 |
The compressive strength of concrete at different ages under standard curing conditions (20 ℃, relative humidity 90%) and curing conditions at 5 ℃ are respectively tested. By adjusting the polycarboxylic acid water reducing agent(commercial Standard type heightThe performance water reducing agent meets the technical requirement of GB8076-2008 in performance indexes, and the method for mixing amount of 20% solid content) ensures that concrete has the same initial working performance.
Application comparative example 1 is a blank control without any early strength agent,
application comparative example 2 is anhydrous sodium sulfate (Na) powder of early strength agent commonly used in the industry2SO4)，
Application comparative example 3 is a solid calcium silicate hydrate sol early strength agent synthesized according to example two of Chinese patent CN 201410593398.
Table 2 shows the compressive strength of the concrete doped with the early strength agents of examples and comparative examples under standard curing conditions, and Table 3 shows the compressive strength of the concrete doped with the early strength agents of examples and comparative examples under curing conditions at 5 ℃. (the early strength agent samples in the inventive examples and comparative examples were all solid contents.)
TABLE 2 compressive Strength of concrete under Standard curing conditions
The results in table 2 show that, compared with a blank control sample (application comparative example 1), the calcium silicate hydrate hollow nanoparticles provided by the invention can remarkably improve the compressive strength of concrete in 6h to 1d, and the strength of concrete in 28d and 90d is also improved to a certain extent, so that the calcium silicate hydrate hollow nanoparticles have a remarkable early strength effect. Compared with sodium sulfate (application comparative example 2), the early strength effect is obviously better under the condition of greatly reducing the dosage. Compared with calcium silicate hydrate sol (application comparative example 3), the early strength effect is similar, and the dosage is only about half of the early strength effect.
Compressive strength at curing conditions of Table 35 deg.C
The results in table 3 show that the calcium silicate hydrate hollow nanoparticle early strength agent provided by the invention can also significantly improve the early-age strength of concrete under the curing condition of 5 ℃. The early strength effect of the calcium silicate sol is far better than that of sodium sulfate, and the dosage of the calcium silicate sol is greatly reduced compared with that of calcium silicate hydrate sol.
Application example 3
For concrete using a large amount of mineral admixture, the compressive strength of the concrete was tested according to the mixing ratio shown in table 4, wherein the amount of the mineral admixture was 45% of the total amount of the cementitious material. The concrete raw material was the same as in application example 1.
TABLE 4 concrete mix ratio (Kg/m)3)
| Cement | Mineral powder | Fly ash | Sand | Crushing stone | Water (W) |
| 247.5 | 112.5 | 90 | 700 | 1140 | 135 |
Table 5 shows the compressive strength of concrete containing a large amount of mineral admixture in which the early strength agent of each example and the early strength agent of the comparative example were incorporated. By adjustingPolycarboxylic acid water reducing agentThe method of the mixing amount ensures that the concrete has the same initial working performance.
Application comparative example 1 is a blank control without any early strength agent, application comparative example 4 is 3% of sodium sulfate and 3% of gypsum in the total using amount of the cementing material, and application comparative example 3 is the solid calcium silicate hydrate early strength agent synthesized according to example two of Chinese patent CN 201410593398.
TABLE 5 compressive strength of concrete with high mineral admixture content under standard conditions
The results in Table 5 show that the invention has obvious promotion effect on the early (12h-3d) strength development of the concrete with the large-amount mineral admixture. Compared with sodium sulfate and gypsum (application comparative example 4), the early strength effect is obviously better under the condition of greatly reducing the dosage. Compared with calcium silicate hydrate sol (application comparative example 3), the early strength effect is similar, and the dosage is greatly reduced.
Claims (4)
1. The preparation method of the early-strength concrete admixture is characterized in that the early-strength concrete admixture is a calcium silicate hydrate hollow nanoparticle dispersion liquid, and the early-strength concrete admixture is prepared by interface reaction of water-soluble calcium salt in a dispersion phase, namely a water phase, and tetraethyl orthosilicate in a continuous phase, namely a non-polar solvent under the action of catalyst ammonia water;
the water-soluble calcium salt is calcium nitrate or calcium nitrite;
the non-polar solvent is cyclohexane, white oil or toluene;
firstly, preparing a water-soluble calcium salt, catalyst ammonia water and water into a solution, then mixing the aqueous solution and a nonpolar solvent containing an emulsifier and a co-stabilizer in a water bath at the temperature of 20-40 ℃, pre-emulsifying by high-speed stirring, and preparing an inverse miniemulsion by ultrasonic emulsification;
then slowly dripping tetraethyl orthosilicate (TEOS) into the emulsion, dissolving the TEOS in the continuous phase, and reacting the TEOS with calcium salt at the interface to generate a calcium silicate hydrate shell layer because catalyst ammonia exists in the dispersed phase when the TEOS is diffused to the interface of the continuous phase and the dispersed phase;
finally forming calcium silicate hydrate hollow nano particles;
the emulsifier adopts a lipophilic nonionic surfactant, and the HLB is 3-8; the dosage of the emulsifier accounts for 3-5% of the whole system.
2. The method of claim 1, wherein the co-stabilizer is polyvinylpyrrolidone (PVP), cetyltrimethylammonium chloride (CTAC) or cetyltrimethylammonium bromide (CTAB); the dosage of the co-stabilizer accounts for 0.5-1% of the whole system; the whole system is referred to as continuous phase + dispersed phase.
3. The method according to claim 2, wherein the emulsifier is one or a mixture of more than two of Span40, Span60 and Span80 in any proportion.
4. A method according to any one of claims 1-3, characterised by the following three steps:
(1) firstly, preparing inverse miniemulsion containing calcium salt and catalyst, and mixing aqueous solution of water-soluble calcium salt and catalyst ammonia water with nonpolar solvent containing emulsifier and co-stabilizer under the conditions of high-speed stirring and ultrasonic emulsification;
the dispersed phase is the water solution of calcium salt and ammonia water; the ammonia water is an important catalyst for the reaction of TEOS and calcium salt, and the dosage of the ammonia water is 1-2% of the mass of TEOS; the mass concentration of the water-soluble calcium salt is 10-20%;
the mass ratio of the continuous phase to the whole system is 50-70%;
mixing the dispersed phase and the continuous phase, placing the mixture in a water bath at the temperature of 20-40 ℃, pre-emulsifying for 15 minutes under high-speed stirring, and then performing ultrasonic emulsification for 15 minutes to finally obtain an inverse emulsion with the particle size of 50-200 nm;
(2) keeping the temperature at 20-40 ℃, dropwise adding TEOS within 5-10 h under the stirring condition, and continuing the heat preservation reaction for 24h after the dropwise adding is finished; the dosage of TEOS is determined by the dosage of calcium salt, and the Ca/Si molar ratio is required to be 2: 1-1: 1;
(3) and raising the temperature to 80 ℃ for demulsification, and collecting the water phase to obtain the dispersion liquid of the prepared calcium silicate hydrate hollow nano particles.
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| CN107673362A (en) * | 2017-10-20 | 2018-02-09 | 武汉理工大学 | A kind of preparation method of hydrated calcium silicate |
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| CN111018394A (en) * | 2019-11-12 | 2020-04-17 | 中交二航武汉港湾新材料有限公司 | Nano crystal nucleus material for UHPC prefabricated part and preparation and application methods thereof |
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